where k >= 0 and each eventi is a legal embedded event form
(see embedded-event-form). These events are evaluated in sequence. A
utility is provided to assist in debugging failures of such execution;
see redo-flat.

ACL2 does not allow the use of progn in definitions. Instead, the
macro er-progn can be used for sequencing state-oriented
operations; see er-progn and see state. If you are using single-threaded
objects (see stobj) you may wish to define a version of er-progn that
cascades the object through successive changes. ACL2's pprogn is the
state analogue of such a macro.

If your goal is simply to execute a sequence of top-level forms, for example
a sequence of definitions, consider using ld instead; see ld.